You can't study consciousness directly in a lab but it's pretty easy to "merge" with others under the right conditions.
For example, here's an old experiment with "mutual hypnosis": two people hypnotizing each other at the same time.
"Psychedelic experiences associated with a novel hypnotic procedure, mutual hypnosis." Am J Clin Hypn. 1967 Oct;10(2):65-78. https://www.ncbi.nlm.nih.gov/pubmed/6080106
Anything which causes entrainment between two dynamic systems is essentially combining them into one dynamic system. E.g. something as simple as deliberately breathing in sync with each other can begin to develop consciousness merging.